Ask the Expert: Should Genetic Tests Be Repeated?

Published on
February 9, 2016

Topics include:
Treatment

In this Ask the Expert segment, Patient Power founder Andrew
Schorr sits down with Dr. Michael Keating of MD Anderson Cancer Center to ask
audience questions about repeat genetic testing. Dr. Keating shares his
thoughts on which tests are essential, when to test again, and whether every
CLL patient should receive the same standard of care from the start.

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Please remember the opinions expressed on Patient Power are not necessarily the views of our sponsors, contributors, partners or Patient Power. Our discussions are not a substitute for seeking medical advice or care from your own doctor. That’s how you’ll get care that’s most appropriate for you.

Andrew Schorr:

What about the need for repeat tests? So often at time of diagnosis, someone has
blood tests and maybe more sophisticated tests, genetic tests, bone marrow
biopsy often. So when do they need to be
repeated and what tests?

Dr.
Keating:

I think the tests that are pretty much essential
for us to evaluate up front, in my experience, the tests that I rely on are
just normal CBC different platican chemistry. The flow cytometry and look at
CB38—it’s not a very robust test, but it does clarify the diagnosis of the CLL
rather than some of the other variance.
The FISH genetics and the mutation status and the Beta2 microglobulin,
and I think they tell us as much as anything else that we have at the present
time. There is a push to get B53
mutation status, but that’s not universally accepted as necessary right
now. The other feature is when do you do
it again. Well, I think you do it when
there’s a change in behavior of the disease because there may be another
genetic mutation that’s occurred at that time and at the start of therapy.

So when you’re getting started on a new therapy, you want to
know really if something different has happened. Some patients that start out for the FISH
test third in Q or negative will subsequently develop an 11Q deletion. And that
tells us a lot about what the disease that we really have to get rid of, and or
a few of them develop a 17p, and we have to think of that too.

Andrew
Schorr:

People wonder well should everyone get standard
treatment first and then see what happens, or do you make decisions to go in
different directions based on those tests?

Dr.
Keating:

You make different decisions based on the tests
because of the biologic behavior and response to the so-called standard therapy—the
situation as the FDA defines standard therapy on an average basis. No patient is average, and every patient
needs good thinking to figure out what is optimal for them. And we have to help
the FDA to get educated in no standard treatment is the right standard
treatment for everyone, and define for them what is best for particular subsets. The problem is that they demand these big
randomized long-term control trials against the standard treatment. And many of
us know that the standard treatment is just not gonna be good.

Please remember the opinions expressed on Patient Power are not necessarily the views of our sponsors, contributors, partners or Patient Power. Our discussions are not a substitute for seeking medical advice or care from your own doctor. That’s how you’ll get care that’s most appropriate for you.